Pretty good workout. Nice relaxed warm up & then for the fartlek segments I was able to maintain a consistent effort, cadence & pace. Did 20 minutes of 3 minutes half marathon effort/1 minute steady effort (5 segments) and then 20 minutes of 4 minutes half marathon effort/1 minute steady effort (4 segments). Got a little fatigued during the last of 3 minute fast segments plus i was also slightly affected by the full sun on the outdoor track. For that reason, I took an extra minute rest after the first 20 minutes. After the extra minute, I resumed the workout and had no trouble finishing the last 20 minutes with pretty much the same effort and pace as the first 20 minutes. Cool down was easy and comfortable. Completed full set of exercise routines after the run..